Have I gone insane? Help me!?

Okay, so lately I have been going what I think is insane. I'll just start laughing my head off and it won't stop for like an hour. I'll just be sitting in my room reading and then I just lose it! I have also been having gruesome nightmares. Like last night, I dream pt that my mom and dad and I were at a drive through and my mom went insane and pulled out my dad's intestines with an airbag and her bare hands! It scared the crap out of me! And whenever somethinging happens, I start to think of the most horrible possibilities. I've also been a bit depressed for no reason. I'm only 12, a little to young to be taking anti depressants. What's happening?